SB2021102803 - Denial of service in Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software
Published: October 28, 2021
Security Bulletin ID
SB2021102803
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Improper Enforcement of Message Integrity During Transmission in a Communication Channel (CVE-ID: CVE-2021-34793)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists in the TCP Normalizer when handling certain TCP segments. A remote attacker can send a specially crafted TCP segment through an affected device and poison MAC address tables.
Successful exploitation of the vulnerability may allow an attacker to perform a denial of service attack but requires the affected device to be operating in transparent mode.
Remediation
Install update from vendor's website.